Problem: $ { 0.2 \times4= {?}} $
${0}$ ${2}$ ${4}$ ${\times}$ ${.}$ ${0.2}\times {4}= {0.8}$ ${8}$ ${0}\times {4}= {0}$ ${0}$ $\text{The top number has 1 digit to the right of the decimal.}$ $\text{The bottom number has 0 digits to the right of the decimal.}$ $\text{The product has 1 + 0 = 1 digits to the right of the decimal.}$ ${.}$ ${ 0.2 \times4= 0.8} $